Apparatus for testing the hardness of materials



L.'l0HNSON AND H. BREARLEY. APPARATUS FOR TESTING THE HARDNESS OF MATERIALS.

APPLICATION FILED S EPT.27, 1919- L 91. IT 2m 4 R mn w M2 m m vll III'II I I ATTORNEY L. JOHNSON AND H. BREARLEY. APPARATUS FOR TESTING THE HARDNESS OF MATERIALS.

APPLICATION FILED SEPT 27, 1919.

Patented July 12, 1921.

- 2 SHEETS-SHEET 2.

- INVENTORS LJohzwozvwH Brantley ATTORNEY UNITED STATES PATENT OFFICE.

APPARATUS ron TESTING THE HARDNESS or MATnnIALs.

Specification of Letters Patent. Patented uly1 2, 1921 Application filed September 27, 1919. Serial No. 326,796.

To all whom it may concern:

Be it known that We, LAWRENCE J oHNsoN and HARRY BREARLEY, both subjects of the King of Great Britain and Ireland, and both residing at Brown Bayleys Steel Works Limited, Sheflield, in the county of Yorkshire, England, have invented certain new and useful Improvements in Apparatus for Testing the Hardness of Materials, of which the following is a specification.

This invention relates to apparatus for testing the hardness of materials with particular reference to apparatus of the'type comprising a hardened steel ball adapted to be forced into contact with the material under a predetermined pressure so that the depth or the diameter of the impression made in the material will be a measure of .its hardness, the applied load being transmitted through a system of levers-to a test weight or its equivalent so that the predetermined pressure may not be exceeded without an indication of such condition being given by movement of the weight.

The object of the present invention is to devise improved apparatus of the above character, whereby a constant predetermined pressure may be readily and with accuracy applied, and if necessary, maintained for.

any'desired length of time.

The invention consists in apparatus of the type referred to, comprising in combination a member supporting a hardened steel ball, a lever carrying said. member, an eccentric connected with said lever for applying the I predetermined load, and a second eccentric connected with said lever and with a second lever or system of levers controlled by a weight or the like.

The invention also consists in the provision of means whereby the predetermined both the shafts g and mmav proved apparatus with a foundation frame work or caslng a of anysuitable character, upon a bed plate I; on whichwe support the material to be. tested and above this bed plate is located a screw threaded spindle 0 or other adjusting member carrying at its lower end a socket e or ,fitting in which .18 mounted the hardened steel ball d. The member 0 is carried by a leverf, as for example, by means of a nut f secured to said lever and is preferablycushioned by means of a spring f arranged between the member f and a tapered washer f engaging an aperturein the casing or framework a. One end of the lever f is connected with aneccentric strap 9 cooperating with an eccentric g mounted in ball or roller bearingsh and adapted to be rotated by a hand lever 71 of sultable form, the lever c and theeccentric both being carried upon the shaft 9 The other end of the lever f is connected with an I eccentric strap in cooperating with the eccentrio is mounted in ball bearingsz' and carried by a shaft m,,it being understood that also be mounted in ball bearings if desired.

Upon the shaft m we mount a'lever the free end of which carries a weight 0, the amount of which is proportioned in relation to the leverageina manner'which is dependent upon the value .of the'predetermined maximum pressure which is to be applied by the hardened steel ball." a I The arrangement is such'that' the necessary load is applied by rotating the hand lever z' and eccentric g sothat through the medium of the lever. ff'the hardened steel .ball is forced under a predetermined pres sure into contact with the "material to be tested, the load being regulated and applied by means of theeccent'ric 7c and the weight and lever connected therewith. Should the pressure tend to rise above the predetermined value, this would at once be indicated by upward movement of the lever n. v

The amount of upward movement allowed to the lever may be limited by a suitable stop but in order to insure that the lever shall not reach the stop in operation and thus allow of the application of a pressure greater than the predetermined maximum we provide a pawl or detent 7) mounted upon the casing 05 and adapted to cooperate with a toothed sector 9 or like member carried. by the hand lever 73, the arrangement being such 'rying said member, an eccentric connected that when the weight lever rises (on the predetermined pressure being reached) it allows the pawl to fall into engagement with the sector upon the hand lever and locks the same against movement in the direction for applying the load.

For the purpose of enabling the predeterminedpressure to be maintained for any desired length of time, we provide a second pawl 1' upon the framing of the machine operable by a pin or stop 8 or other means so-that when the predetermined pressure is reached the pawl may be made to engage the sector of the hand lever thus locking the a: releasing the load. 1

Claims t 1. Apparatus of the typereferred to, comprising incombination a hardened steel ball, amember supporting said ball, a lever carrying said member, an eccentric connected with saidleve'r'for applying the predetersame a ainst rotation in the direction for 'mined'load'and a second eccentric connected with said lever and with a second lever or lever" ystem controlled by a weight, sub;

stantially asdescribed.

2. "Apparatus of the type referred to'comprising in combination a hardened steel ball, a member carrying same, alever carrying said members, an eccentric connected with said lever, means connected to said lever adapted to impose a predetermined resistance to movement thereon in order to apply a predetermined load upon said hardened steel ball and means for maintaining the predetermined load for any desired length of time, substantially as described.

- Apparatus'of the type referred to, com prising in combination a hardened steel ball, a member supporting said ball, a lever carwith said lever for applying the predetermined load, a second eccentric connected with saidflever and with a second lever or lever system controlled by a weight, substantially as described. Q

4:. Apparatus of the type referred to, comprising in combination a hardened steel ball,

a member supporting said ball, alever carr in sa1d member an eccentric connected y D 7 i i with said lever for applying the predetermined load, asecond eccentric connected with said lever and witha second lever or lever system-controlled by a weight, and means prising in combination a hardened steel ball, '1

a member supporting said ball, a lever carrying sa1d member, means for applying a load to sa1d member,'means for preventlng said load. from rising above apredetermined maximum, and means for maintaining said' of time, substantially as described. I

7. Apparatus of the type referred to, compredetermined load for any desired length prising a hardened steel ball, a member sup- 4 porting said ball, a lever carrying said. memher, an eccentric at one end of" said leverf,a hand lever in connection with said eecen tric, a second eccentric at the other end of said lever, a second lever connected with said last-mentioned eccentric, a weight controlling said lever, a toothed sector movable withsaid hand lever and a pawl for preventing, when necessary, movement of said sector in the direction for releasing theload, substantially as described.

8. Apparatus of the type referred to, comprising a hardened steel ball, a member supporting said ball, a lever carrying said member, an eccentric at one end of said lever, a hand lever in connection with said'eccentric, a second eccentric at the other end of said lever, a second lever connectedwith said last-mentioned eccentric, a weight controlling said lever, a'toothedsector movable with said hand lever and a pawl controlled by said weight-controlled lever so that said pawl will prevent movement of said toothed sector in the' diredtion for applying the load when the weight controlled lever commences to rise, substantially asdescribed.

In testlmony whereof we have signed our names to thisspecification;

LAWRENCE JOHNSON; HARRY BREARLEY. 

